FAUNISTIC RESULTS. 441 



of marked affinity with any other fauna. In fact,, the differences are more evident 

 than the resemblances. Even in the case of two such neighbouring localities as the 

 Maldives and Ceylon, Mr. E. T. BROWNE, after considering the figures, writes : " the 

 Medusoid fauna of Ceylon is quite distinct from that of the Maldives." But the fact 

 that the genera and species of GARDINER'S and AGASSIZ'S successive expeditions to 

 the Maldives " were quite distinct," and that there is a well-marked difference 

 between the two collections " which is quite as great as if they had come from 

 localities a thousand miles apart" (BROWNE) shows that we must not attach too 

 much importance to such differences. Seasons and methods of collecting must be 

 taken into account, and we have probably still much to learn in regard to each of 

 these faunas. 



The HYDROIDA are fairly abundant at Ceylon, and some of them are of large size 

 (see Plate II., figs. 5 and 6). Outside the Indian Ocean the affinities of the Ceylon 

 forms are distinctly with those of Australian seas out of 43 species, 11 extend to 

 Australia, and only nine of the other species are found beyond the Ceylon seas ; four 

 of these occur in the West Indies, and only one in the Mediterranean. 



The ALCYONARIA form a rich collection, dealt with in three reports (Nos. XIX., 

 XX., and XXVIII.). Miss PRATT points out the similarity with the Maldive fauna, 

 nine species of the fleshy forms, out of 17, being common to the two districts; but 

 Professor ARTHUR THOMSON, dealing with the Gorgonoid, Pennatulid, and other 

 non-fleshy forms, lays stress upon the great difference between the present collection 

 and those from Zanzibar (CROSSLAND), Maldives (GARDINER), New Britain (WILLEY), 

 and the deeper waters of the Indian Ocean (ALCOCK). I believe this merely indicates 

 that the Alcyonarian fauna of these regions is so rich that we are still far from having 

 completed the survey. Each new expedition brings in an abundant harvest, and in 

 our present state of knowledge it is probably more profitable to base any tentative 

 conclusions upon resemblances in the fauna rather than upon differences which may 

 merely be due to negative evidence. 



Many of the species are familiar Indo-Pacific forms, a few are represented in the 

 Malay region ; but perhaps the closest affinity is with the Red Sea fauna, on the one 

 hand, and with that of Australian seas on the other. As in the case of so many 

 other groups, at least one species is represented in the West Indies. 



CORALS are, of course, exceedingly abundant round the coast of Ceylon. The reef- 

 building forms were not specially collected and have not been reported on, but over 

 30 common species have been brought home. There are in the collection about 

 21 species of Solitary Corals, five of which are described as new, along with two new 

 genera, rRhodocyathus and Cyathotrochus. 



The ACTINIARIA, although not reported on, have been examined by Mr. SOUTHWELL, 

 who finds about 14 species, of which several are probably undescribed forms. A 

 beautiful green, colonial form, Zoanthus shacJcletoni, is very abundant on the reef at 

 Galle and in some parts of the Gulf of Manaar. A species of Palythoa (P. tuber- 



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